First Author | Kim NH | Year | 2014 |
Journal | J Invest Dermatol | Volume | 134 |
Issue | 4 | Pages | 1075-1082 |
PubMed ID | 24335901 | Mgi Jnum | J:208059 |
Mgi Id | MGI:5560848 | Doi | 10.1038/jid.2013.478 |
Citation | Kim NH, et al. (2014) Reduced MiR-675 in exosome in H19 RNA-related melanogenesis via MITF as a direct target. J Invest Dermatol 134(4):1075-82 |
abstractText | H19 non-coding RNA downregulation stimulates melanogenesis in melasma patients. However, its mechanism is unclear. In this study, the potential role of a H19 microRNA, miR-675, in melanogenesis was examined. Real-time PCR using cultured normal human skin keratinocytes, melanocytes, and fibroblasts with or without H19 knockdown showed accompanying changes between expression levels of H19 and those of miR-675 in keratinocytes. MiR-675 was also detected in concentrated culture supernatants and showed expression levels parallel with those of cell lysates. In addition to RNase resistance, FACS analysis showed anti-CD63-positive exosomes in culture supernatants, suggesting miR-675 could be released extracellularly and delivered to neighboring cells without degradation. In western blot analysis, the miR-675 mimic reduced the expression of microphthalmia-associated transcription factor (MITF) and phosphorylation of cAMP-responsive element-binding protein, extracellular signal-regulated kinase and apoptosis signal-regulating kinase, whereas these expressions were increased by the miR-675 inhibitor. Although H19 was not a miR-675 target, luciferase reporter assay showed a direct binding of miR-675 to 3'-untranslated region of MITF. In addition, localized in vivo miR-675 overexpression in mouse using a cationic polymer transfection reagent showed reduced mRNA expression levels of MITF, tyrosinase, tyrosine-related protein-1 (Trp-1), and Trp-2. Collectively, the results suggest that miR-675 derived from keratinocytes could be involved in H19-stimulated melanogenesis using MITF as a target of miR-675. |